<template>
  <view>
    <!-- 搜索组件 -->
    <my-search @click="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧的滑动区 -->
      <scroll-view scroll-y="true" class="left-scroll-view" :style="{height: wh + 'px'}">
        <block v-for="(item,index) in cateList" :key="index">
          <view :class="['left-scroll-view-item',index === active ?'active': '']" @click="activeChanged(index)">{{item.cat_name}}</view>
        </block>
        
      </scroll-view>
      <!-- 右侧的滑动区 -->
      <scroll-view scroll-y="true" class="right-view-container" :style="{height: wh + 'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2,index2) in cateLevel2" :key="index2">
          <!-- 二级分类 -->
          <view class="cate-lv2-title">
            / {{item2.cat_name}} /
            <!-- 三级分类 -->
            <view class="cate-lv3-list">
              <view class="cate-lv3-item" v-for="(item3,index3) in item2.children" :key="index3" @click="gotoGoodsList(item3)">
                <image :src="item3.cat_icon"></image>
                <text>{{item3.cat_name}}</text>
              </view>
            </view>
          </view>
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
 import badgeMix from '@/mixins/tabbar_badge.js'
 export default {
   mixins: [badgeMix],
    data() {
      return {
        //当前设备可用的高度
        wh:0,
        cateList:[],
        active: 0,
        cateLevel2:[],
        scrollTop:0
      };
    },
    onLoad() {
      const systInfo = uni.getSystemInfoSync()
      // console.log(systInfo);
      this.wh = systInfo.windowHeight - 50
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const { data:res } = await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status !== 200) return uni.$showMsg()
        this.cateList = res.message
        // console.log(this.cateList);
        this.cateLevel2 = res.message[0].children
      },
      activeChanged(index){
        this.active = index
        
        this.cateLevel2 = this.cateList[index].children
        
        this.scrollTop = this.scrollTop === 0 ? 1 : 0
      },
      //跳转到商品详情页面
      gotoGoodsList(item){
        // console.log(item);
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?cid=' + item.cat_id
        })
      },
      gotoSearch(){
        uni.navigateTo({
          url: '/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;

  .left-scroll-view {
    width: 120px;

    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;

      // 激活项的样式
      &.active {
        background-color: #ffffff;
        position: relative;

        // 渲染激活项左侧的红色指示边线
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left: 0;
          top: 50%;
          transform: translateY(-50%);
        }
      }
    }  
  }
  .right-view-container{
      background-color: #ffffff;
    }
}
.cate-lv2-title {
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
}
.cate-lv3-list {
  display: flex;
  flex-wrap: wrap;

  .cate-lv3-item {
    width: 33.33%;
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    // justify-content: center;
    align-items: center;

    image {
      width: 60px;
      height: 60px;
    }

    text {
      font-size: 12px;
    }
  }
}
</style>
